Deciphering the diversity and history of New World nightjars (Aves: Caprimulgidae) using molecular phylogenetics Sigurðsson, Snorri Cracraft, Joel Zoological Journal of the Linnean Society 2014 2014-03-12 170 3 506 545 Sennett 1888 [881,1162,1194,1215] Aves Caprimulgidae Nyctidromus Animalia Caprimulgiformes 35 541 Chordata species merrilli  Previously N. a. merrilli, and includes individuals assigned to N. a. insularis, N. a. intercedens, and N. a. yucatanensis. It is elevated to full species status and is the sister species of a clade containing  N. albicollisand  N. derbyanus.  Diagnosis   Nyctidromus merrilliis intermediate in size, and the plumage is both lighter and greyer than  N. albicollisand  N. derbyanus, with a slate-grey coloration on the crown and back being particularly noticeable. There are also conspicuous black patterns on the coverts of  N. merrilli, which in both  N. albicollisand  N. derbyanustend to be browner. Some individuals in arid areas of Mexicoare slightly more reddish in colour, but overall the three named forms within  N. merrilli( insularis,  merrilli, and yucatanensis) are similar to one another.  Comments See comments in previous section on  N. derbyanus.